Monitoring Weekly Monitoring: During the last week (24th-31st July) there was no significant rainfall experienced and dry conditions prevailed throughout the country. Monthly Monitoring: During July, southern half of the island experienced a below average rainfall with an increased below average particularly in the Western and South Western regions. It clearly reflects the deficit of the South West Monsoon rainfall up to now. The rest of the island experienced an above average rainfall with a higher intensity in the Trincomalee district while some parts of the Moneragala district also experienced an above average rainfall.
7 Day Prediction: For the coming week an accumulated rainfall of 5 mm - 15 mm is predicted particularly in some parts of the South Western region, Western region. IMD WRF Model Forecast & IRI forecast: 1mm- 8mm rainfall is predicted for some parts of Puttalam district, Colombo, Gampaha, Kalutara and Galle districts on the 3rd of August. Rainfall is predicted for the same districts with an increased rainfall of about 36mm particularly for Colombo, Gampaha and Kalutara districts on the 4th August. No rainfall is predicted for the rest of the country. NOAA models forecast up to 20 mm of rainfall till the 5th of August for the entire island.
1 Month Prediction: Overall a continuation of the existing conditions shall be expected. A low rainfall with fluctuations shall be expected. The maximum rainfall shall not exceed 6mm. Western slopes- Rainfall fluctuations shall be expected. Wet conditions shall not be expected and the maximum rainfall shall not exceed 7mm. Rainfall is not predicted after the 24th of August. Eastern slopes- The Rainfall shall increase rapidly till the 8th of August followed by a decreasing trend with minor fluctuations till the 27th of August. The maximum rainfall shall not exceed 7mm. Northern region- A rapid increase of rainfall shall be observed till the 6th of August followed by a decreasing trend with some fluctuations. The maximum rainfall shall not exceed 6mm. Seasonal Prediction: As per IRI Multi Model Probability Forecast for August 2012 to October 2012, issued in July 2012, there is a 60%-70% probability for temperature to be above normal in the country. There is 40% probability for rainfall to be climatological.
Inside this Issue
a. Daily Satellite Derived Rain fall Estimates
b. Monthly Rain fall Estimates
c. Decadal (10 Day) Satellite Derived Rainfall Estimates
d. Weekly Average SST Anomalies
a. NCEP GFS Ensemble 1-7 day predictions, NOAA, CPC,USA
b. IMD WRF Model Forecast
c. Weekly precipitation forecast (IRI)
d. 1 month experimental predictions by Paul Roundy and L. Zubair
e. Seasonal Predictions from IR